From 17429f7578c76409af483cd14926618e88458de5 Mon Sep 17 00:00:00 2001
From: Tokunori Ikegami <ikegami.t@gmail.com>
Date: Tue, 12 Sep 2023 23:42:32 +0900
Subject: [PATCH] ioctl: Add debugging feature to show command outputs

Signed-off-by: Tokunori Ikegami <ikegami.t@gmail.com>
---
 src/libnvme.map  |  2 ++
 src/nvme/ioctl.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++-
 src/nvme/ioctl.h | 12 +++++++++++
 3 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/src/libnvme.map b/src/libnvme.map
index faabd721..1765bc65 100644
--- a/src/libnvme.map
+++ b/src/libnvme.map
@@ -8,6 +8,8 @@ LIBNVME_1_6 {
 		nvme_root_release_fds;
 		nvme_subsystem_get_iopolicy;
 		nvme_subsystem_release_fds;
+		nvme_set_debug;
+		nvme_get_debug;
 };
 
 LIBNVME_1_5 {
diff --git a/src/nvme/ioctl.c b/src/nvme/ioctl.c
index b9710b3d..ec0ac6b6 100644
--- a/src/nvme/ioctl.c
+++ b/src/nvme/ioctl.c
@@ -13,9 +13,11 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <inttypes.h>
 
 #include <sys/ioctl.h>
 #include <sys/stat.h>
+#include <sys/time.h>
 
 #include <ccan/build_assert/build_assert.h>
 #include <ccan/endian/endian.h>
@@ -23,6 +25,8 @@
 #include "ioctl.h"
 #include "util.h"
 
+static bool nvme_debug;
+
 static int nvme_verify_chr(int fd)
 {
 	static struct stat nvme_stat;
@@ -86,13 +90,62 @@ static int nvme_submit_passthru64(int fd, unsigned long ioctl_cmd,
 	return err;
 }
 
+static void nvme_show_command(struct nvme_passthru_cmd *cmd, int err, struct timeval start,
+			      struct timeval end)
+{
+	printf("opcode       : %02x\n", cmd->opcode);
+	printf("flags        : %02x\n", cmd->flags);
+	printf("rsvd1        : %04x\n", cmd->rsvd1);
+	printf("nsid         : %08x\n", cmd->nsid);
+	printf("cdw2         : %08x\n", cmd->cdw2);
+	printf("cdw3         : %08x\n", cmd->cdw3);
+	printf("data_len     : %08x\n", cmd->data_len);
+	printf("metadata_len : %08x\n", cmd->metadata_len);
+	printf("addr         : %"PRIx64"\n", (uint64_t)(uintptr_t)cmd->addr);
+	printf("metadata     : %"PRIx64"\n", (uint64_t)(uintptr_t)cmd->metadata);
+	printf("cdw10        : %08x\n", cmd->cdw10);
+	printf("cdw11        : %08x\n", cmd->cdw11);
+	printf("cdw12        : %08x\n", cmd->cdw12);
+	printf("cdw13        : %08x\n", cmd->cdw13);
+	printf("cdw14        : %08x\n", cmd->cdw14);
+	printf("cdw15        : %08x\n", cmd->cdw15);
+	printf("timeout_ms   : %08x\n", cmd->timeout_ms);
+	printf("result       : %08x\n", cmd->result);
+	printf("err          : %d\n", err);
+	printf("latency      : %lu us\n",
+	       (end.tv_sec - start.tv_sec) * 1000000 + (end.tv_usec - start.tv_usec));
+}
+
+void nvme_set_debug(bool debug)
+{
+	nvme_debug = debug;
+}
+
+bool nvme_get_debug(void)
+{
+	return nvme_debug;
+}
+
 static int nvme_submit_passthru(int fd, unsigned long ioctl_cmd,
 				struct nvme_passthru_cmd *cmd, __u32 *result)
 {
-	int err = ioctl(fd, ioctl_cmd, cmd);
+	struct timeval start;
+	struct timeval end;
+	int err;
+
+	if (nvme_get_debug())
+		gettimeofday(&start, NULL);
+
+	err = ioctl(fd, ioctl_cmd, cmd);
+
+	if (nvme_get_debug()) {
+		gettimeofday(&end, NULL);
+		nvme_show_command(cmd, err, start, end);
+	}
 
 	if (err >= 0 && result)
 		*result = cmd->result;
+
 	return err;
 }
 
diff --git a/src/nvme/ioctl.h b/src/nvme/ioctl.h
index 47d8625e..2a6c4621 100644
--- a/src/nvme/ioctl.h
+++ b/src/nvme/ioctl.h
@@ -3855,4 +3855,16 @@ int nvme_zns_append(struct nvme_zns_append_args *args);
  */
 int nvme_dim_send(struct nvme_dim_args *args);
 
+/**
+ * nvme_set_debug - Set NVMe command debugging output
+ * @debug:	true to enable or false to disable
+ */
+void nvme_set_debug(bool debug);
+
+/**
+ * nvme_get_debug - Get NVMe command debugging output
+ *
+ * Return: false if disabled or true if enabled.
+ */
+bool nvme_get_debug(void);
 #endif /* _LIBNVME_IOCTL_H */